wscall-protocol 0.1.1

Shared protocol types and frame codec for WSCALL
Documentation
# wscall

WSCALL is a lightweight WebSocket API framework with a custom binary frame protocol, a reusable Rust server crate, a reusable Rust client crate, and a facade crate for consumers that prefer a single dependency.

## Workspace Layout

The repository is now organized as a Cargo workspace:

```text
crates/
	wscall-protocol/
	wscall-server/
	wscall-client/
	wscall/
```

Each crate has a clear responsibility:

1. `wscall-protocol`: shared frame codec, envelope types, file attachment model, and protocol errors.
2. `wscall-server`: reusable WebSocket server framework with routes, filters, validation, exception mapping, and server push events.
3. `wscall-client`: reusable client SDK with request correlation, event ACK correlation, and server event subscriptions.
4. `wscall`: facade crate that re-exports protocol plus optional server and client APIs behind features.

## Protocol Summary

Each WebSocket binary message is encoded as:

```text
| frame_len:u32 | message_type:u8 | encryption:u8 | payload |
```

Transport behavior:

1. Plaintext mode stores JSON directly in `payload`.
2. `ChaCha20` and `AES256` modes store `12-byte nonce + ciphertext` in `payload`.
3. The payload limit is `10 * 1024 * 1024 - 6`, which keeps the full WSCALL frame within `10 MiB`.
4. File parameters use JSON references plus inline Base64 attachments.

## Use As Crates

Depend on only what you need:

```toml
[dependencies]
wscall-server = "0.1.1"
wscall-client = "0.1.1"
```

Or use the facade crate:

```toml
[dependencies]
wscall = { version = "0.1.1", features = ["full"] }
```

## Quick Start

Minimal server:

```rust
use serde_json::json;
use wscall::WscallServer;

#[tokio::main]
async fn main() -> Result<(), Box<dyn std::error::Error>> {
	let mut server = WscallServer::new();

	server.route("system.echo", |ctx| async move {
		Ok(json!({
			"route": ctx.route(),
			"params": ctx.params(),
		}))
	});

	server.listen("127.0.0.1:9001").await?;
	Ok(())
}
```

Minimal client:

```rust
use serde_json::json;
use wscall::WscallClient;

#[tokio::main]
async fn main() -> Result<(), Box<dyn std::error::Error>> {
	let client = WscallClient::connect("ws://127.0.0.1:9001/socket").await?;
	client
		.on_connected(|event| async move {
			println!("connected: {}", event.url);
		})
		.await;
	client
		.on_disconnected(|event| async move {
			println!("disconnected: {}", event.reason);
		})
		.await;
	let response = client
		.call("system.echo", json!({ "message": "hello" }), Vec::new())
		.await?;

	println!("response: {response}");
	client.close().await?;
	Ok(())
}
```

Client reconnect behavior:

1. Unexpected disconnects trigger automatic reconnect attempts.
2. The first retry waits 3 seconds.
3. Each later retry increases the delay by 1 second.
4. The retry delay is capped at 30 seconds.
5. Calling `close()` stops reconnect attempts.

Runnable end-to-end quick start:

```bash
cargo run -p wscall --example quick_start --features full
```

## Run The Demos

Start the demo server:

```bash
cargo run -p wscall --example demo_server --features server
```

In another terminal, run the demo client:

```bash
cargo run -p wscall --example demo_client --features client
```

The demos exercise:

1. `system.echo` API.
2. `files.inspect` API with inline attachment.
3. `chat.message` event emit and broadcast.
4. `chat.history` API query.
5. End-to-end ChaCha20 frame encryption using the demo key wired in both examples.

## Quality Gates

Recommended checks before publishing or merging:

```bash
cargo fmt --all --check
cargo clippy --workspace --all-features --all-targets -- -D warnings
cargo test --workspace --all-features
```

## Publishing Checklist

Before publishing the crates to crates.io:

1. Confirm the configured `repository` and `homepage` metadata still match the canonical repository.
2. Run the quality gates locally.
3. Update all workspace crate versions and internal dependency pins to the target release version.
4. Run `cargo package` for `wscall-protocol` to validate the root dependency crate.
5. Publish in dependency order: `wscall-protocol`, `wscall-server`, `wscall-client`, then `wscall`.
6. After each publish, wait for the crates.io index to catch up before packaging or publishing the next dependent crate.

For any release that introduces a new unpublished dependency version, downstream crates such as `wscall-server`, `wscall-client`, and `wscall` must still be published in dependency order so crates.io can resolve the freshly published versions.

See `RELEASE.md` for a release sequence that matches this dependency chain.

Version history is tracked in `CHANGELOG.md`.

## Current Constraints

1. `ChaCha20` and `AES256-GCM` are implemented in `FrameCodec`; the demos still default to `ChaCha20`.
2. Attachments are inline Base64 and suited to small files.
3. Large-file chunking is not part of the current core protocol.
4. The published crate and code identifiers have been renamed to `wscall`.